Field of the Invention
The present invention relates to a new and useful device for holding coils of tie material and more particularly relates to an improved spool adaptor for holding coils of elongated tie material.
In recent years tie ribbon, much of which is manufactured from wire embedded in plastic or paper, has been used on an ever increasing scale for tying packages such as bread bags. In an automated system the tie material or ribbon comes wound on a spool or reel which rotatably mounts on a spindle of a tie wrapping machine. Desired lengths of the ribbon are automatically unwound and severed.
The spools used in the past have been unitary in design with two circular flanges mounted integrally to the ends of a cylindrical, central wrapping core. These spools, in addition to being expensive, produce a handling problem and the accumulation of large numbers of spools presents a disposal problem.
Advances in the art have made it possible to use a flangeless spool comprising basically a central core about which the wire or tie ribbon is wound. The coil is made stable and secure by twisting the ribbon periodically during the winding operation.
However, direct use of the flangeless spool poses many problems. In most applications, a sufficient frictional drag must be provided on the spool to prevent the tie material from unraveling. The central core alone might not provide enough exposed surface area to apply a braking force. Furthermore, even if the ribbon is twist wound on the core, during handling, loading on the tie wrapping machine or during a wrapping operation, it is possible for the ribbon to slip off the sides of the flangeless spool and wrap around the spindle on which the spool is mounted. This causes down time in the tie wrapping operation while the ribbon is being untangled.
To solve the above-mentioned problems, it has been suggested in U.S. Pat. No. Re. 31,015, issued to Doyle A. Moore on Aug. 24, 1982, which is a reissue of U.S. Pat. No. 4,117,988, issued on Oct. 3, 1978, to use a spool adaptor having a tubular center section and a pair of circular flange sections mounted to each end of the center section. One of the flange sections is removable so that the adaptor can accept spools of coiled tie material. The center section of the adaptor is segmented to form expandable legs. A collet expander is threaded onto a shaft inserted centrally through the center section and tightened to cause the legs of the segmented center section to move radially outwardly from the center section and engage the central core of the spool. In this manner the spool rotates with the adaptor without slipping.
The adaptor disclosed in the above patents has many inherent disadvantages. The device is mechanically complex and employs a number of parts. For this reason it is expensive to manufacture. Only a trained worker would be skilled enough to assemble the device or to break it down into its component parts to remove or replace a worn element.